WARNING: The videos in this story contain graphic images

Anyone tempted to dismiss the angry, in-your-face tactics of the Black Lives Matter movement — “What’s their problem, anyway? Don’t all lives matter?” — should spend a little time browsing the special litigation section of the U.S. Department of Justice.

You will, for example, find the sorry tale of Baltimore’s police department.

Baltimore’s officers have for years indulged in a pattern of unconstitutional stops, searches and arrests, blatantly targeting black people.

Of the 410 Baltimore residents stopped or searched at least 10 times over six years, 95 per cent were black. One black man was stopped 30 times in that period, and never once arrested or charged with anything. (Incidentally, when BPD officers did stop or search a white person, they were twice as likely to find contraband.)

The report, released earlier this year, described the tendency of Baltimore police to quickly and brutally deal with anyone foolish enough to speak up for his or her rights, especially blacks.

It laid out a pattern of excessive force; juveniles, it said, were treated as roughly as adults.

‘His spine just broke by itself, right?’

And then there was the grim case of Freddie Gray, 25, whose neck was broken in Baltimore police custody last year.

Gray was tackled by police who found him suspicious, and, after noticing a small knife clipped inside his pocket, arrested and charged him.

He went into a police van shackled. By the time he arrived at the station, his spinal cord was severed, and he was comatose.

The state’s attorney, a woman named Marilyn Mosby, decided to lay charges. First of all, she said, Gray’s folding knife was not illegal (and remember, this is a country where it is legal not just to bear arms, but in many states, to carry a pistol openly). Second, she determined, someone had to be held accountable for the death of a young black man who, as far as she could tell, had broken no law, other than walking around while black.

Then a familiar system clicked in. Police protested angrily. Conservatives accused Mosby, who is black, of everything from hating police to breaking the law herself. The familiar blue wall went up.

And one after another, until Mosby gave up and dropped the case, the officers involved were set free by judges.

Black Americans were told: sorry, unfortunate, but the courts have spoken.

As Prof. Eddie Glaude, head of the African American studies program at Princeton University, put it: “I’m supposed to be kind of comfortable with the fact that you know … Freddie Gray’s spine cracked on its own. You know, as if that happened without anybody doing it? That’s what the courts seemed to suggest, that his spine just broke by itself, right?”

Glaude’s disgust is shared by millions of other black Americans. Thanks to the explosive use of phone video, something loathed by police, what’s been going on for hundreds of years in America is now on YouTube for every American to judge for him or herself.

It’s ugly, it’s frightening, and the question “would this have happened to a white person?” looms over it all.

There’s Philando Castile in Minnesota, shot to death through his car window by a policeman while trying to produce the concealed carry permit for the weapon he’d informed the officer he was legally carrying.

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Philando Castile shooting aftermath 9:49

There’s Eric Garner, 43, choked to death by police in Long Island, N.Y., after being rousted for selling loose cigarettes. As he died, he croaked that he couldn’t breathe. The head of New York’s police union contemptuously declared that anyone who can say he can’t breathe can obviously still breathe.

There is Walter Scott, shot in the back after trying to flee an officer in South Carolina who’d pulled him over for a broken tail light. The cop, unaware that he was being recorded, then cuffed the corpse and later appeared to drop something on the ground beside him.

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Police dashcam footage moments before shooting of Walter Scott 4:02

There was Alton Sterling, shot several times at close range by Baton Rouge police who’d already pinned him down and immobilized him.

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U.S. police shooting caught on camera 0:27

And so many others, always justified by police.

But there’s always one episode, or person, that becomes a proxy for everything else. And the one that tipped over the official manure spreader was Laquan McDonald, who, in October 2014, ran across the wrong policeman in Chicago.

The rallying cry of Laquan McDonald

McDonald was a 17-year-old with a record of truancy and a juvenile sheet of petty offences, not unusual for a product of Chicago’s poor, despair-soaked black neighborhoods.

Initially, police responded to a report that he was breaking into cars; when they confronted him, he stupidly broke a cruiser’s window, and used a jackknife to vandalize one of its tires. Within minutes, he was dead.

Police immediately issued the usual claim of self-defence. McDonald, they said, had appeared crazed, and had lunged at an officer with his knife. The shooter, Officer Jason Van Dyke, told investigators he feared for his own life.

Demonstrators gather after marching at the Louisiana Capitol on July 9, 2016. (Mark Wallheiser/Getty Images)

Van Dyke’s fellow officers backed him 100 per cent. No charges were laid. And that’s the way the story stood for nearly a year.

Unfortunately for the police, though, there are access to information laws in America.

Jamie Kalven, a white Chicago civil rights activist, doggedly pursued the details of the autopsy on McDonald, and when he finally obtained them, the rotten smell was evident.

The matter finally went to court, and in November 2015, a little more than a year after the shooting, a judge ordered the video released.

There were actually several videos, and some of them were found to have been tampered with. There was also footage from the camera of a nearby Burger King, which police had quickly confiscated and erased.

Nonetheless, what video remained proved what Kalven had suspected: a far-reaching official coverup.

McDonald, it turned out, was walking away from police when Officer Van Dyke suddenly ran up and opened fire. There was a pause, and Van Dyke began firing again into the prone body.

The state’s attorney, after more than a year of considering the case, charged Van Dyke with murder the very day the video was released.

It all lit a smoking national fuse. Black Americans from coast to coast watched in inchoate anger, and the Black Lives Matter coalition, which had already made a national impression following the killing of another black man in Ferguson, Mo., earlier in 2015, mobilized, sensing a national moment was at hand.

Lamon Reccord stares at a Chicago police officer as he and others march through Chicago’s Loop on Nov. 25, 2015, one day after murder charges were brought against police officer Jason Van Dyke in the killing of 17-year-old Laquan McDonald. (Charles Rex Arbogast/Associated Press)

Chicago Mayor Rahm Emanuel recognized a disaster when he saw it. He apologized and conceded Chicago police racism, choking up in public.

‘You hear it over and over and over again — bad police, bad police, bad police. That’s the narrative you hear.’-Dean Angelo, president, Fraternal Order of Police, Chicago

At Chicago’s Fraternal Order of Police, union president Dean Angelo felt betrayed. Betrayed by pusillanimous politicians, and under pressure from black activists he clearly thinks distort reality.

“You hear it over and over and over again — bad police, bad police, bad police. That’s the narrative you hear,” he told me.

“And we have politicians here that call me on the phone and say, ‘How you doin’, we’re worried about you guys and you do such a great job. Um, but you know, make sure you don’t tell anybody I called. But just so you know, I’ve got your back.’ And I’m like, ‘Hell you do.'”

There was certainly no sympathy in Washington. The Justice Department got involved and will almost certainly add Chicago’s police to the long list of departments under special legal sanction.

Death by video

But Laquan McDonald had become an icon, and protests kept intensifying nationwide, as more videos of black men being killed by police seemed to pop up weekly. By early last summer, during a Black Lives Matter protest in Dallas, an angry lone gunman opened fire on police, killing several.

Similarly, police in Baton Rouge were lured into a deadly trap after the killing of Alton Sterling. Other gunmen attacked police in Tennessee, Georgia and Missouri.

Black Lives Matter suddenly found itself forced to repudiate violence its members hadn’t committed, while conservatives used the episodes to denounce the movement as cop-killing anarchists.

Just about no one, of course, asked what the white Americans who publicly tote around assault rifles and handguns would do if whites were being systematically rousted and disproportionately gunned down by police.

Well, comedian Bill Maher did: “I’m surprised somebody did not fire back sooner,” he said on MSNBC, stoking conservative fury.

A man protesting the shooting death of Alton Sterling is detained by law enforcement near the headquarters of the Baton Rouge Police Department on July 9, 2016. (Jonathan Bachman/Reuters)

At Princeton this month, Glaude told me the young black people leading demonstrations now grew up “witnessing a level of death by video” he never experienced at that age.

Glaude says this new generation is done with hopeful engagement and patiently waiting for change: “I do know that a lot of folks in our communities were talking about what happened in Dallas before Dallas happened.”

Asked what that means, Glaude shoots back: “That they keep killing our kids. That these kids are going to wind up killing them, right? That’s a barbershop conversation, right? And I’m not urging that, I’m just saying this is the reality of what do you, what do you do, right, when you comply, and you still end up dead?”

Arguments about arms

Others, more radical than Glaude, have suggested that black Americans take the advice the National Rifle Association offers all Americans: arm themselves systematically, and begin carrying weapons to protests in the many states that now legally permit “open carry.”

Heaven knows white gun activists do that.

After all, says the NRA, “an armed society is a polite society,” and no one needs official politeness more than black Americans.

But everyone knows what a disaster that could be. In the eyes of American police, armed blacks are entirely different than armed whites. The Black Panthers armed themselves in the ’60s, and were crushed, two of their leaders assassinated in their sleep by Chicago police.

A demonstrator sits in front of a street fire during a protest that broke out after a grand jury in Ferguson, Miss., decided not to indict a white police officer over the fatal shooting of Michael Brown. (Stephen Lam/Reuters)

If law-abiding black Americans began collectively availing themselves of their Second Amendment rights, the way the overwhelmingly white membership of the NRA does, how long would it take before some militarized police force, somewhere in America, opened fire, claiming self-defence?

It may indeed be that Black Lives Matter had a moment on their hands after the video of Laquan McDonald’s killing was made public.

But they’ve since run into powerful forces they must have known were there, and that doesn’t just mean Trump-style “alt-right” conservatives.

Police, mocking their message, have begun using the hashtag #BlueLivesMatter in reply.

And of course, Americans who see themselves as “colour-blind” like to say “All Lives Matter.” Even Hillary Clinton has used that line, in a black church, no less.

Blissfully oblivious?

The truth is, even after all the video of all the killings, and all the special litigations of the U.S. Justice Department, America remains a deeply segregated nation, and white Americans remain happily oblivious, counting on police to protect them, willing to overlook a few excesses if that’s what it takes.

Leaving Chicago on a warm autumn night last month, I suddenly found myself in a moving ocean of Bears fans on South Michigan Avenue.

In a parking lot near my hotel, a tailgate party was revving up.

It was quite the sight: a bunch of white sports fans having a hell of a time, barbecuing dogs and burgers and knocking back beer right on one of the busiest streets of the city, in the open.

I flipped the frame, as someone like Glaude would suggest, and tried to imagine what would happen if a bunch of black people showed up in one of the most expensive neighbourhoods of Chicago and started setting up outdoor cooking equipment and drinking openly.

To ask that question is to answer it. The thing is, almost nobody does ask.

Back in Chicago, police union president Angelo leans back amid years of police mementos and grip-and-grin photos.

“We’re not racist,” he says. “We don’t like anybody. We don’t care who you are.”